The New York Times today (December 16, 07) publishes a series of letters in response to Richard E. Nisbett's Op Ed article " All Brains are the Same" from December 9th. The original article and the letters focus on the relations between genetic endowment, intelligence, and IQ.
These letters are exemplary (with the exception of one which is flat out stupid, accusing Nisbett of political correctness). They are worth studying because they demonstrate how informed comment can cut to the heart of issues discussed in the public arena and really make a profound contribution.
Stephen Murdoch, a historian of IQ, writes:
I.Q. tests were created in the early 1900s before scientists had sufficient understanding of the brain or genetics. They were cobbled together with no real intelligence theory — and they have changed very little over time.
If we want intelligence tests, we need to devise new ones based on actual scientific theory rather than Victorian and Progressive Era puffery.
Paul Coleman, a senior Alzheimer's researcher, writes:
It is not the genetic DNA in a cell that determines what a cell is and how it performs; it is, rather, which genes are turned on and when. Turning a gene on or off can be controlled by a wide variety of factors in life: toxins, learning, disease, hormones, drugs, diet — the list is numberless.
We now know enough about the fine structure of the brain, the proteins involved and the roles they play in learning, cognition, memory and other components of intelligence to understand that the DNA of genes are, generally, many steps removed from determining these capacities.